General astronomy

General astronomy

Contributors in General astronomy

General astronomy

a galaxy with a smooth, rounded appearance. Early large burst of star formation long ago used up all of their original gas and dust. Star orbits are aligned in more random directions and have greater ...

emission line spectrum

Astronomy; General astronomy

bright lines in a spectrum that are produced by hot, thin (low-pressure) gases. Made by electrons jumping down closer to the nucleus of the atom.

epicycle

Astronomy; General astronomy

a device in Ptolemy's Earth-centered model that makes a planet execute a small circular motion around a point that is itself in a circular orbit around the Earth. It was used to explain retrograde ...

equation of state

Astronomy; General astronomy

the relation that describes the state or condition of a material as determined by how the temperature, density, and pressure depend on each other in the material.

Equation of Time

Astronomy; General astronomy

a relation that describes the difference in time between the meridian crossings of the mean Sun and the actual Sun.

equinox

Astronomy; General astronomy

point on the sky where the ecliptic and the celestial equator intercept. When the Sun is at the equinox point, it is on the celestial equator and we have 12 hours of daylight. Vernal (spring) ...

equivalence principle

Astronomy; General astronomy

states that there is no experiment a person could conduct in a small volme of space that would distinghish between a gravitational field and an equivalent uniform acceleration. This principle is the ...